Esophageal pH monitoring is performed if you are having problems with your upper digestive tract. It helps your doctor determine if stomach acid is entering your esophagus.

The is the hollow muscular tube that connects your throat to your stomach. It is lined with a soft mucous membrane, which protects the esophagus from damage.

The esophagus plays a very simple role in the digestive process. It conveys food from your throat to your stomach. After the mouth (and teeth), this is the second portion of your digestive system. It’s frequently exposed to sharp or abrasive food items, such as:

  • shards of bone
  • tough plant leaves
  • potato chips

You doctor may recommend this test if you have symptoms of gastroesophageal reflux disease (GERD). The test measures how often and for what length of time acid enters your esophagus.

GERDis a chronic disease of the digestive system caused by bile or acid backing up from your stomach. This causes the following symptoms:

  • heartburn: acid indigestion in your stomach, chest, or abdomen
  • regurgitation: acid (and sometimes food) back-flowing into your throat or mouth
  • dyspepsia: burping, bloating, or nausea after eating

Many people experience these symptoms from time to time. Your doctor may suspect you have GERD if you are experiencing these symptoms more than twice each week. Your doctor may also want to test you if your symptoms are so severe that they interfere with your daily life.

This test may be performed in combination with an endoscopy of your upper gastrointestinal (GI) tract. During an endoscopy, your doctor inserts a flexible scope with attached camera into your esophagus, to look for causes of GERD.

In infants, esophageal pH monitoring can also be used to check for digestive disorders that could cause excessive crying.

You doctor will ask you to avoid eating or drinking for 12 hours before the test. You will also need to stop smoking during this time.

Some prescription medications can affect the results of testing. Your doctor may tell you to stop taking them for up to two weeks before the test. Some drugs that can affect the test results include:

  • adrenergic blockers (drugs that relax the muscles of your bladder and prostate)
  • anticholinergics (drugs used in the treatment of spastic GI tract disorders)
  • certain antacids
  • alcohol
  • cholinergics (drugs that produce the same effects as the parasympathetic nervous system)
  • corticosteroids (steroid hormones)
  • H2 blockers (drugs used to block histamine effects on your stomach, such as Zantac)
  • proton pump inhibitors (drugs used to reduce gastric acid production)

Only stop taking medications if your doctor advises you to do so.

Your doctor will pass a fine tube down your throat into your esophagus. A tiny pH meter is at the end of the tube. It calculates the amount of acid present.

You will return home with the tube in place. For the next 24 hours, you will keep a diary that tracks:

  • what time you eat and drink
  • what food you eat and drink
  • what time you lie down or get up
  • any symptoms you experience

The following day, you will return to the hospital to have the tube removed. Data from the device will be combined with your notes to make a diagnosis.

Children are usually required to stay in hospital for the entire 24 hours.

After your doctor interprets the data collected from the test, they’ll be in touch to discuss your results.

An abnormal result generally means there is too much acid in your esophagus. This could be related to:

  • heartburn
  • GERD
  • scars in your esophageal lining tissue
  • dysphagia (difficulty swallowing)
  • Barrett’s esophagus (damaged cells in your lower esophagus)
  • reflux esophagitis (inflammation of your esophagus)

If your doctor suspects esophagitis, you may need additional tests. These will typically include a GI endoscopy or barium swallow.

There are no significant risks related to an esophageal pH monitoring test. Rare complications include:

  • inhaling vomit, if the tube causes vomiting
  • an irregular heartbeat during tube insertion

Many people are able to manage the discomfort of heartburn by:

  • making changes to their diet
  • getting more exercise
  • stopping smoking
  • reducing or eliminating caffeine and alcohol consumption
  • taking over-the-counter medications

If you have GERD, these solutions may offer only temporary relief. Your doctor may recommend prescription medications to control your symptoms.

Surgery may sometimes be recommended if your GERD is caused by structural damage to your esophagus. The sphincter that closes the bottom of your esophagus may need to be repaired. Surgery can also be used to scar your esophagus so that it no longer causes pain.